Saturday, December 14, 2013
Houseplants: Part II: Scale Insects
Sorry for the length of time between posts: Thanksgiving and end-of-semester busy-ness absorbed my time. So, to continue on about houseplants: sometimes I find these little brown bumpy things on my plants and you might too: in the photo above these are identified by arrows. What are they?
These are actually scale insects, sometimes just called scale, also leaf scale. These armored bugs most often arrive to your home on newly acquired plants and slowly make their presence known. They attach to the leaves of your plant and slowly suck the juices out of the leaf. A severe infestation, one you are unlikely to miss, unless you never look at your plants, can kill the plant. And, in juvenile form, they are tiny and mobile (adults are sessile, so stay put).
What to do? First, really, check out plants before you bring them home, looking at both sides of the leaves, stems and branches. If you see scale, don't buy the plant and let the staff and the store know. Next, when you do bring plants home, isolate them from other plants for a couple of weeks. I find this hard to do as my space for plants is pretty full. If you do find scale, move the plant to a sink. Remove all adults by hand (they are pretty easy to rub off) or you can use a cotton swab dipped in rubbing alcohol to remove them. Rinse away the sticky residue left by the insects. Then, to get those pesky juveniles, spray with insecticidal soap, and spray again once a week for two weeks. Continue to monitor your plants: if scale breaks out again, repeat the process and increase your vigilance!
Happy houseplant gardening!